Mana Base

The Mana Base page (/manabase) scores your deck's land count and colored-source supply against Frank Karsten's source-count method. The verdict is computed directly in DeckFlow — there is no AI round-trip needed to tell you whether the mana base holds up.

Step 1 — Load A Deck

Pick one of two inputs:

  • Public URL — paste an Archidekt or Moxfield deck link.
  • Paste decklist — paste a list, one card per line (e.g. 4 Island). Set and collector number are optional but help cards resolve to the exact printing. Include a Commander section header (your export usually does) so the analyzer can pin and weight your commander.

Add an optional Deck name to label the report.

Deck type and commander importance

  • Deck type — Casual (default; Karsten's full land target) or cEDH (a lower land count in the competitive ~28–32 band, assuming heavy fast mana).
  • How important is your commander? — Central (must cast as early as possible every game, e.g. Brago), Standard (matters, cast when convenient), or Low (optional / late value). Central holds the commander's colors to a stricter threshold; it does not change the land target. Both selectors persist when you re-analyze.

Reduced / alternative costs (optional)

Some cards cost far less than their printed mana value: pitch / free spells (Force of Will), board-scaling self-reducers (Blasphemous Act {8}{R} that you usually cast for {R}), and evoke / suspend. DeckFlow auto-detects these and pre-fills the "Reduced / alternative costs" box — one card per line as Card Name: cost, for example:

Force of Will: 0
Blasphemous Act: {R}

Edit or clear any line you disagree with (the cost is what the card effectively costs you, not its printed cost). The value is a mana cost, so it can change colors, not just lower the number: 0 makes a card behave like a true 0-cost spell (it stops demanding its colors), while {R} keeps one red pip. An applied override flows through the whole verdict — the castability simulation, the on-curve turn, and the per-color source findings — and the affected rows are flagged with a *. Leave the box empty to score every card at its printed cost.

Then press Analyze Mana Base. Cards resolve through Scryfall by exact printing first, so alternate or flavor names still match; anything unresolved is listed separately.

Step 2 — Read The Report

The result panel shows:

  • Health verdict — a four-tier scale that grades the mana base, not the curve:

    • Excellent — land count is within one of target and no color has any shortfall.
    • Solid — the base works with only minor notes: within a land or two of target, or a few demanding cards that cast late because they are expensive (a curve problem the mana base can't fix). Those demanding cards are still listed by name (e.g. Solid — 1 demanding card: Grand Abolisher (77%)) so you can decide whether they're worth the strain.
    • Workable — one contained color problem the base can fix: a single color short by a source or two, or one color with more color-starved cards than a small ratio of that color.
    • Needs work — a real, broad shortage: the deck is two-plus lands short, a color is short by several sources, or two or more colors are short.

    Crucially, a card that casts late only because of its mana cost (not its colors) never fails the base — that is a curve issue, surfaced in the castability table, not a mana-base fault. The source requirements are mulligan-aware (they account for Commander's free first mulligan) and clamped to Karsten's table as a ceiling, so a tight double-pip like a turn-two {W}{W} is neither flagged against an inflated requirement nor pushed past the math.

  • Biggest fix — one actionable line, chosen so it never contradicts the health/land read: it points at the color that is genuinely short (add ~N sources), else at the land count (add ~N lands), else at trimming the top end — and never tells you to add a negative or "remove" source count.

  • Land count — your actual land total vs. the count Karsten's math recommends for your curve (cEDH lowers that target), with an OK / short note.

  • Color findings — for each color: how many effective sources you run (duals, any-color rocks, and fetchlands are credited to every color they can make), the toughest spell driving the requirement, how many of that color's cards are under-supported, and their mean castability. The weakest color is highlighted; a lone hard-to-cast bomb still surfaces even if the rest of the color is fine.

  • Castability (Casual mode) — a table of each real spell's estimated chance to be cast on its on-curve turn, worst-first, with a low / ok / good chip, its average delay (how many turns late it typically becomes castable — on curve when it lands on time, else +N.N turns), and what's limiting it (mana, color: X, or mana + color). Your commander is pinned at the top. Mana rocks, dorks, and lands are counted in the math but not listed as rows. A * next to a card's mana value means a reduced / alternative cost from your overrides was applied. cEDH mode hides this table.

The castability number comes from a Monte-Carlo simulation (it plays out thousands of games with a London mulligan), so read it as a ranking aid, not a guarantee.

Step 3 — See The Formula

Two collapsible panels show exactly how the verdict was reached:

  • How the analysis works — the methodology (Karsten's land regression, the cEDH adjustment, and the castability simulation), shown even before you analyze.
  • This deck's numbers — the land-target formula with your deck's values plugged into every term, the per-color source tally, and the simulation parameters. Use it to audit why a color or a card was flagged.

Step 4 — Optional: Land-Swap Prompt

The math tells you what is short, but not which lands to add for your specific deck. The optional "Want specific land swaps?" block builds a small ChatGPT / Claude prompt framing the deficits. This is the only part of the workflow that needs an AI — the verdict itself does not.

Notes

  • The analyzer is tuned for Commander / cEDH singleton decks.
  • The land count uses Frank Karsten's published source-count work; the castability estimate is DeckFlow's own simulation, cross-checked against community calculators including Salubrious Snail.
  • The same scoring engine is available from the CLI as the manabase command (the castability + mode UI is web-only).
  • This tool can be turned off by an administrator; when it is, this help topic is hidden too.